What is coal Share with your friends Share 1 Alabh Manjul answered this coal is black colored stone on burning it releases polluting smoke it takes several years to form so it cannot be formed under labrotary condition it is formed by the decaying of vegetation HELPS YOU A LOT 1 View Full Answer Simi Gracia answered this a combustible black or dark brown rock consisting chiefly of carbonized plant matter, found mainly in underground seams and used as fuel. "two bags of coal" 0